There is an increasing level of awareness concerning the emission of mercury and other volatile metals such as cadmium and thallium, certain volatile organic compounds (VOCs), acid gases such as HCl, and dioxin/furans from industrial plants such as cement manufacturing facilities. With this heightened level of awareness, more stringent environmental regulations are being adopted to lower emissions from these industrial plants. Consequently, there is an interest in developing systems for controlling emissions to meet newly proposed regulations, and that is an object of the present invention.